Division 6.6.8.2 For diagonal (Bias-ply) tyres:F1
The thickness of original material above the breaker shall be ≥ 0,00 mm.
The average thickness of new material above the buffed casing line shall be ≥ 2,00 mm.
The combined thickness of original and new material beneath the base of the grooves of the tread pattern shall be ≥ 2,00 and ≤ 5,00 mm.